NASA discovers 26 new alien planets in 11 solar systems

The findings nearly double the number of bona fide planets found outside our solar system by the Kepler space observatory.

"Prior to the Kepler mission, we knew of perhaps 500 exoplanets across the whole sky," Doug Hudgins, Kepler program scientist at NASA headquarters in Washington, said in a statement. "Now, in just two years staring at a patch of sky not much bigger than your fist, Kepler has discovered more than 60 planets and more than 2,300 planet candidates. This tells us that our galaxy is positively loaded with planets of all sizes and orbits."

The newly detected worlds vary in size from 1.5 times the radius of Earth to larger than Jupiter; 15 of the 26 planets fall between Earth and Neptune in size. While all of the planets tightly orbit their parent stars, more research will be required to determine which worlds are rocky like Earth, and which have thick, gaseous atmospheres like Neptune, the scientists said.